We are planning to move students' and teachers' computers to Ubuntu 18.04
It has a nicer to use Desktop and is also the currently supported Ubuntu
It supports ROS Melodic (and ROS Melodic does not support the old Ubuntu)
Follow Ubuntu's own installation instructions to install a clean copy of Ubuntu
As Robotis is still on Ubuntu 16.04 and ROS Kinetic we have to amend their instructions a little
Our baseline is http://emanual.robotis.com/docs/en/platform/turtlebot3/pc_setup/